Victoria Rose, prosecuting, said Taylor was arrested after the mother of one of his victim’s uncovered worrying messages on her daughter’s mobile phone.

The court heard 200,000 messages were found on Taylor’s computer and mobile phone, including many that were of an illegal, sexual nature.

Investigators uncovered the fact Taylor had used search terms to find indecent images of children.

Ms Rose said Taylor used a variety of identities and email addresses to chat with young girls on social media websites.

One of the identities Taylor used was that of Liam Payne, a member of the boy band One Direction.

In one case, Taylor asked a young teenage girl for a naked picture of herself after he convinced her he was the popstar.

Taylor told the girl, who was excited to speak to him, he would call her after she sent the picture and said the song he was currently writing would be about her.

The court heard that Taylor also pretended to be a teenage girl himself and used a picture of a young female to trick other victims.

Taylor also admitted distributing indecent images of children to other paedophiles on the internet and encouraged the commission of a sexual assault on a toddler.

Her Honour Judge Adrienne Lucking said a conversation between Taylor and a man in the USA in which they described how they wanted to abuse the child was “sadistic and revolting”.

The court heard that Taylor also tricked a teenage girl into sending an indecent image of herself after he told her he would post a naked picture of her on social networks and on pornographic sites.

Judge Lucking said: “There was clearly a tormenting and sadistic tone in the messages you sent to her.

“It could not have been more embarrassing, distressing or humiliating for a teenage girl.”

Police also uncovered 42 of the most serious category A indecent images of children, 13 category B and 82 category C.

They also found an image of extreme pornography involving Taylor performing a sexual act with a dog that he had then “bragged about” online.

Dominic Woolard, mitigating, said his client was someone of “limited sexual and relationship experience”.

Mr Woolard said he had been bullied at school, had few friends, and used the internet world as a form of “escapism”.

He said; “That escapism that started as a taboo world then led onto the criminal acts.”

Judge Lucking said the fact Taylor had pretended to be an international popstar demonstrated “predatory” behaviour.

She said: “One of your victims really believed you were Liam Payne.

“You used a false identity to cover up your real age and identity.

“It shows the lengths you were prepared to go to ensure young girls engaged and spoke with you.”

Judge Lucking said she believed Taylor had a “predatory sexual interest in young girls” and exhibited “deceptive and manipulative behaviour” to take advantage of their vulnerability.

Taylor was sentenced to five years in prison for encouraging the commission of a sexual assault on a child, two years for distributing indecent images of children, five years for blackmail, eight months for possessing the indecent images and four months for possessing the extreme pornographic image. All these sentences will be served concurrently.

He was given a four-year jail sentence for inciting a child to engage in sexual activity as well as a four-year extended licence period because he was assessed as “dangerous”.

Judge Lucking said Taylor must serve at least two thirds of his four-year sentence before he will be considered for parole, meaning he is likely to serve two years and eight months in custody before being considered for release on licence.

He was also made the subject of an indefinite sexual harm prevention order and will be placed on the sex offenders’ register.